Oil burner



Nov. 13, 1928. 1,691,541

l. E. CARLSON ET AL OIL BURNER Filed Aug. 17, 1925 4 Sheets-Sheet 2 fizvenioni Nov. 13, 1928.

l. E. CARLSON ET AL OIL BURNER Filed Aug. 17, 1925 4 Sheets-Sheet 4 1 JM rv Z Z Wm ll m Patented Nqv. 13, 1928.

UNITED, STATES PATIENT. OFFICE. v

IWAN n. cmson, or WATERTOWN, AND LOREN R. CHURCHILL, or WOLLASTON', MASSACHUSETTS.

OIL BURNER.

Application filed August 17, 1925. Serial No. 50,614.

This invention relates to hydrocarbon burners, and particularly to a burner of the induced draft type wherein the forced draft of a blower is utilized. to inject the liquid. fuel into the combustion chamberof the burner. Such burners are commonly used for domestic heating purposes where safety, economy, convenience and efiiciency are prime requisites. Our burner is of this general type, and in it we have endeavored to provide for the maximum of safety and efficiency in a construction which is at once both simple and economical in installation and upkeep.

To this end, we so arrange the usual gas pilot with which practically all burners of this type are equipped that it is not only protected against accidental extinguishment, as by draft or otherwise, but can be readily cleaned without removal from the combustion chamber of the burner. In addition, we incorporate a further feature of safety in that in .our construction the arrangement is such that should for any reason the fuel fail to be properly vaporized, the supply of both fuel and air to the combustion chamber will be automatically shut off until such failure has been remedied.

. In order to insure delivery of the fuel to thecombustion chamber of the burner in a form best suited for combustion, we preferably preheat the air before mixture with the fuel. The fuel delivers intmthe combustion chamber of the burner through a Venturi tube, which enters said chamber at one side of the vertical axis thereof and delivers the mixture against the wall of the chamber. This imparts to the mixture a rotary swirling effect within thechamber whereby it is thoroughly atomized. I

These and various other features of advantage in both structure and result which will appear more particularly hereinafter, are'secured in the burner of the present invention, the construction and operation of which, together with a selected embodiment thereof which well illustrates the principles involved and is itself a form found satisfactory in use and well adapted to the requirements of manufacture, are described and illustrated in the accompanying specification and drawings, and the characteristic features of novelty particularly pointed out In assume to shut OK the supply of both fuel and air to the combustion chamber, should the fuel not be properly vaporized.

Fig. 5 is a detail plan iew of the combustion chamber, and particularly showing the protected mounting'of the gas pilot.

Figs. 6 and 7 are sections on approximatethg lines 66 and 7,-7, respectively. of

Fig. -8 is a sectionon line 88, of Fig. 6, and

Fig. 9 is a section on approximately the line 9-9, of Fig. 5.

We have-indicated at 1 a portion of the approximately the firebox wall of a heating plant, such as a furnace or steam or hot water boiler. Adjustably mounted on the supports 2 within the heating plant is the combustion chamber 3 of our oil burner, which is of the induced draft, gravity feed, type embodying a motordriven blower fau t and a fuel supply pipe 5 leading from agravity tank (not shown).

According to our invention, the air of combustion is preheated before mixture with the fuel. To this end, the air intake pipe 6 for the fan is carried into the firebox of the heating plant, as shown in 1, and the wall of the heating lant is opened, as indicated at 7 in said fi gure to permit a draft of air across the firebox. The preheated air thus drawn'into the air intake pipe 6 is circulated through the fan chamber of the fan and blown by the fan through the delivery pipe 8 into the combustion chamber 3 of the turi 9 so that the draft of air through said pipe 8 is provided pipe 8 and tube 9 draws the fuel from said uel pipe through a fuel feed device F into the combustion chamber 3 of the burner.

The fuel supply pipe 5 is provided with both a manual shut-off valve 10 and an automatic shut-off valve 11, and the lead wires L to the motor M of the fan have the usual line switch S, which is manually operated, and an automatic circuit breaker 12. The purpose of this construction is to automatically shut-oil the supply of fuel and air to the burner should for any reason the fuel not be properly vaporized in the combustion chamber 3, as may happen where the pilot light 13 is accidentally extinished. Under such conditions, the raw el drains through the bottom of the combustion chamber into an overflow pipe 11. This pipe has a fuel trap 15 therein and beyond said trap empties into an overflow receptacle 16 which is suspended by a flexible connection 17 operatively connected to 'both the automatic fuel shut-off valve 11 and the automatic circuit breaker 12 for a the fan motor.

Such connections are detailed in Figs. 3 and 4 which show, respectively, both the normal and the safety positions of the parts. By reference to these figures, it will be noted that the cable 17 is passed through one arm 17 of a counter-balance valve operating lever 18 which is fulcrumed between its ends at 19 and has its other arm 20. connected to the automatic fuel shut-off valve 11. The

upper end of the cable 17 is connected beyond the lever 18.to one arm 21 of the automatic circuit breaker 12, which circuit breaker is pivoted at 22 and has a make and break arm 23 adapted to close and open the circuit in the lead wires L according to whether or not the overflow receptacle 16 is filled or empty (see Figs. 3 and 4).

According to our invention, the delivery 'end of the mixture inlet pipe 8 is brought into the combustion chamber 3, which is of circular form, at a point closely adjacent the wall thereof, and in a plane which is normal to the vertical axis of said chamber. This insures that the mixture will be iven a swirling efiect within the combustion c amber, as is indicated diagrammatically by the arrows in Fig. 8, and this effect is accentuated by the converging form of the opening 24, which-is cored into said chamber 3 to receive the inner end of the mixture de livery pipe 8 (see Fig. 7). By 'this arrangement we obtain a thorough atomization of the fuel discharging into the combustion chamber.

In order to protect the gas pilot 13 from accidental extinguishment, we mount said pilot'within a web 25, (Fig. 5), formed on the combustion chamber and arrange a baflie 26 adjacent thereto so as to deflect the draft from said flame. The gas supply pipe 27 to said pilot is provided with a fitting 28 whereby the pipe may be disconnected and a cleaning wire 29 (Fig. 9) entered through the fitting 28 to remove any carbon or soot which might clog the pilot.

The operation is as follows: With the line switch S closed and the manual fuel valve 10 open, current is supplied to the fan motor M and fuel is allowed to pass along the pipe 5. The fan draws preheated air from over the fire box of the heating plant through the air intake pipe 6 and delivers it into the combustion chamber 3 through the pipe 8, such delivery acting to draw fuel from the pipe 5 into the Venturi tube 9 and the mixture is delivered to and ignited within the combustion chamber by the pilot light which is constantly burning. So long as the fuel is properly vaporized within the combustion chamber, the parts remain in the position of Fig. 3, but should for any reason the vaporization not be complete, the unvaporized fuel will flow through the overflow pipe 14 into the receptacle 16. When this receptacle fills to a depth sufiicient to overbalance the counter-weighted lever 18, the automatic fuel shut-off valve 11 and the automatic circuit breaker 12 will both be operated to simultaneously shut off the flow of fuel through the pipe 5 andto stop the fan, as -shown in Fig. 4.

If desired, he air intake pipe 6 may be provided between the heating plant and the fan with a fresh air inlet opening controlled by a slide 100 so as to permit varying quantities of air at cellar temperature to be delivered to the fan along with the preheated air from the heating plant, according to the adjustment of said slide.

Various modifications in the construction and operation of my device may obviously be resorted to all without departing from the spirit of my inventionif within the limits of the appended claims.

hat we therefore claim and desire to secure by Letters Patent is:

1. In an oil burner, a combustion chamber adapted to be mounted within a heating plant, an air pipe delivering to said chamber, a Venturi tube in said air pipe, a fuel pipe entering said air pipe and terminating within said Venturi tube, a blower operatively connecting with said air pipe, an air intake for sa d blower having its inlet end disposed within the heating plant in juxtaposition to said combustion chamber, whereby the air is pre-heated before delivery to said blower, said Venturi tube entering the chamber laterally thereof whereby the mix-' 2. In an oil burner, a combustion chamber adapted to be mounted within a heating rplant, an air pipe delivering to said chamber laterally thereof, a Venturi tube in said 6 air pipe, a fuel pipe enterin said air pipe .and'terminating'wlthin said %7enturi tube, a blower operatively connecting with said air pipe, an air intake for said blower having its inlet end disposed within the heating '10 plant in juxtaposition to said combustion chamber whereby the air is preheated before delivery to said blower, said Venturi tube entering the chamber laterally thereof whereby the mixture delivered against the chamber wall is given a swirling effect within the chamber, a as pilot within said chamber, and a bafile etween the discharge end of said Venturi tube and said pilot.

In testimony whereof we aflix our signatures.

LOREN R. CHURCHILL. IWAN E. QARLSON. 

